Nitrogen Retention in Headwater Streams: The Influence of Groundwater-Surface Water Exchange

Groundwater-surface water (GW-SW) interaction lengthens hydraulic residence times, increases contact between solutes and biologically active surfaces, and often creates a gradient of redox conditions conducive to an array of biogeochemical processes. As such, the interaction of hydraulic patterns and biogeochemical activity is suspected to be an important determinant of elemental spiraling in streams. Hydrologic interactions may be particularly important in headwater streams, where the extent of the GW-SW mixing environment (i.e., hyporheic zone) is proportionately greater than in larger streams. From our current understanding of stream ecosystem function, we discuss nitrogen (N) spiraling, present a conceptual model of N retention in streams, and use both of these issues to generate specific research questions and testable hypotheses regarding N dynamics in streams

The non-adoption of supply chain management

This is an Accepted Manuscript of an article published by Taylor & Francis in Construction Management and Economics on 10th October 2013, available online: http://wwww.tandfonline.com/10.1080/01446193.2013.830186.Largely taken for granted within the UK construction sector has been a view that supply chain management theory is robust, relevant and reliable. As such it has formed a substantial aspect of previous and contemporary policy and government funded research. Despite this, the general view of its development and diffusion over the last 15 years within the construction industry has been problematic. Coincidentally, prevailing debates within the supply chain management academic community point to the lack of unified theory, models of diffusion and strong connections to organization theory. Using Straussian grounded theory, iterations between data and organization theory provided a fresh perspective on the development and diffusion of supply chain management in construction. This inductive research provided contextually rich explanations for development and diffusion that explicitly connected with and drew upon robust, relevant and reliable theories of institutions, innovation diffusion, triads, quasifirms and mechanisms of organizational governance. These explanations challenge the simplistic assumption that chains and networks of organizations are holistically managed and controlled by any single organization or institution in the construction industry. The debate therefore shifts away from proselytizing supply chain management towards research that explores the rigour, relevance and reliability of supply chain management assumptions in construction. The gap between industry practice and policy is exposed and the question is posed: to what extent policy and practice do, or should, constitute a recursive relationship.© 2013 Taylor & Francis

Food processing technology : principles and practice

505 p. : il.; 24 cm